/* Semiconductor Stack Disruptors - lab-specific styles
   Inherits /css/style.css (navy gradient body, fixed header, footer).
   Adapts the editorial composition (numbered sections, stack diagram,
   incumbent vs challenger layer panels, tiered conviction list) to the
   canonical.cc system: navy gradient background, Aeonik display type,
   white paper cards with slate ink, orange accents. */

:root {
    --sem-navy: #1e3a8a;
    --sem-navy-deep: #162456;
    --sem-accent: #f97316;        /* orange-500 */
    --sem-accent-soft: #fdba74;
    --sem-positive: #15803d;
    --sem-on-navy-faint: rgba(255, 255, 255, 0.55);
    --sem-on-navy-soft: rgba(255, 255, 255, 0.75);
    --sem-on-navy-strong: rgba(255, 255, 255, 0.92);
    --sem-card-bg: #ffffff;
    --sem-card-bg-2: #fafafa;
    --sem-ink: #0a0a0a;
    --sem-ink-soft: #1f2937;
    --sem-ink-muted: #475569;
    --sem-ink-faint: #94a3b8;
    --sem-rule: rgba(15, 23, 42, 0.08);
    --sem-rule-strong: rgba(15, 23, 42, 0.16);
    --sem-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
}

/* ============ HERO ============ */
.sem-hero {
    padding: 8rem 0 3rem;
    text-align: left;
}

.sem-hero-content {
    max-width: 1100px;
    margin: 0 auto;
}

.sem-eyebrow {
    display: inline-block;
    font-family: var(--sem-mono);
    font-size: 0.72rem;
    font-weight: 500;
    letter-spacing: 0.18em;
    color: var(--sem-accent-soft);
    text-transform: uppercase;
    margin-bottom: 1.5rem;
}

.sem-title {
    font-size: clamp(2.5rem, 6.5vw, 5.2rem);
    font-weight: 300;
    line-height: 1.05;
    letter-spacing: -0.025em;
    color: #ffffff;
    max-width: 22ch;
    margin: 0 0 1.5rem;
}
.sem-title em {
    font-style: normal;
    color: var(--sem-accent-soft);
    font-weight: 400;
}

.sem-subtitle {
    font-size: clamp(1.05rem, 1.4vw, 1.25rem);
    font-weight: 400;
    line-height: 1.6;
    color: var(--sem-on-navy-soft);
    max-width: 64ch;
    margin: 0 0 2.5rem;
}
.sem-subtitle a { color: var(--sem-accent-soft); text-decoration: underline; text-underline-offset: 3px; }
.sem-subtitle a:hover { color: #ffffff; }

.sem-meta {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem 2.5rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    max-width: 64rem;
}
.sem-meta-item { display: flex; flex-direction: column; gap: 0.25rem; }
.sem-meta-key {
    font-family: var(--sem-mono);
    font-size: 0.65rem;
    letter-spacing: 0.12em;
    color: var(--sem-on-navy-faint);
    text-transform: uppercase;
}
.sem-meta-val {
    font-family: var(--sem-mono);
    font-size: 0.78rem;
    color: var(--sem-on-navy-strong);
    line-height: 1.4;
}

/* ============ TL;DR STRIP ============ */
.sem-tldr {
    padding: 3.5rem 0;
    background: rgba(255, 255, 255, 0.04);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(4px);
}
.sem-tldr-intro {
    font-family: var(--sem-mono);
    font-size: 0.75rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--sem-on-navy-faint);
    margin-bottom: 1.75rem;
    text-align: center;
}
.sem-tldr-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2.5rem;
}
.sem-tldr-item {
    padding: 0.5rem 0.25rem;
    border-radius: 0.4rem;
    transition: transform 0.15s;
}
.sem-tldr-item:hover {
    transform: translateY(-2px);
    background: rgba(255, 255, 255, 0.03);
}

.sem-stat {
    font-size: 3rem;
    font-weight: 300;
    color: #ffffff;
    line-height: 1;
    letter-spacing: -0.02em;
    margin-bottom: 0.7rem;
}
.sem-stat em {
    font-style: normal;
    color: var(--sem-accent-soft);
    font-weight: 400;
}
.sem-stat-unit {
    font-size: 1.5rem;
    color: var(--sem-on-navy-soft);
    font-weight: 300;
    margin-left: 0.1em;
}

.sem-tldr-label {
    font-size: 0.92rem;
    line-height: 1.5;
    color: var(--sem-on-navy-soft);
}
.sem-tldr-label strong { color: #ffffff; font-weight: 500; }

/* ============ SUB-NAV ============ */
.sem-subnav {
    position: sticky;
    top: 72px;
    z-index: 40;
    background: rgba(30, 58, 138, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 0.65rem 0;
}
.sem-subnav-list {
    list-style: none;
    display: flex;
    gap: 1.5rem;
    margin: 0;
    padding: 0;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}
.sem-subnav-list::-webkit-scrollbar { display: none; }
.sem-subnav-list li { flex: 0 0 auto; }
.sem-subnav-list a {
    display: inline-block;
    font-family: var(--sem-mono);
    font-size: 0.72rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--sem-on-navy-soft);
    padding: 0.5rem 0.9rem;
    border-radius: 999px;
    transition: background 0.15s, color 0.15s;
    text-decoration: none;
    white-space: nowrap;
}
.sem-subnav-list a:hover { background: rgba(255, 255, 255, 0.08); color: #ffffff; }
.sem-subnav-list a.active { background: rgba(255, 255, 255, 0.12); color: #ffffff; }

/* ============ SCENE BASE ============ */
.sem-scene {
    padding: 5rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    scroll-margin-top: 130px;
}
#stack, #upstream, #equipment, #design, #tiers, #methodology { scroll-margin-top: 130px; }

.sem-section-label {
    font-family: var(--sem-mono);
    font-size: 0.72rem;
    letter-spacing: 0.18em;
    color: var(--sem-accent-soft);
    text-transform: uppercase;
    font-weight: 500;
    margin-bottom: 1.25rem;
}
.sem-section-num { color: var(--sem-on-navy-faint); margin-right: 0.4rem; }

.sem-scene-h2 {
    font-size: clamp(1.85rem, 3.4vw, 2.85rem);
    line-height: 1.1;
    letter-spacing: -0.02em;
    font-weight: 300;
    color: #ffffff;
    margin: 0 0 1.4rem;
    max-width: 30ch;
}
.sem-scene-h2 em {
    font-style: normal;
    color: var(--sem-accent-soft);
    font-weight: 400;
}

.sem-lede {
    font-size: 1.05rem;
    line-height: 1.6;
    color: var(--sem-on-navy-soft);
    margin: 0 0 1.5rem;
    max-width: 72ch;
}
.sem-lede a { color: var(--sem-accent-soft); text-decoration: underline; text-underline-offset: 3px; }
.sem-lede a:hover { color: #ffffff; }

/* ============ DIAGRAM CARD ============ */
.sem-diagram-wrap {
    margin-top: 2.5rem;
    padding: 2rem;
    background: var(--sem-card-bg);
    border-radius: 0.75rem;
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.35), 0 2px 6px rgba(0, 0, 0, 0.1);
    overflow-x: auto;
}
.sem-diagram-wrap svg {
    display: block;
    margin: 0 auto;
    width: 100%;
    max-width: 1080px;
    height: auto;
}
.sem-diagram-legend {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    margin-top: 1.5rem;
    flex-wrap: wrap;
    font-family: var(--sem-mono);
    font-size: 0.7rem;
    color: var(--sem-ink-muted);
    text-transform: uppercase;
    letter-spacing: 0.12em;
}
.sem-diagram-legend .swatch {
    display: inline-block;
    width: 10px;
    height: 10px;
    border-radius: 2px;
    vertical-align: middle;
    margin-right: 0.4rem;
}

/* ============ POV BLOCK (on navy) ============ */
.sem-pov {
    margin: 2rem 0 0;
    padding: 1.5rem 1.6rem;
    border-left: 3px solid var(--sem-accent);
    background: linear-gradient(90deg, rgba(249, 115, 22, 0.06), transparent 80%);
    border-radius: 0 0.5rem 0.5rem 0;
}
.sem-pov-label {
    font-family: var(--sem-mono);
    font-size: 0.7rem;
    color: var(--sem-accent);
    text-transform: uppercase;
    letter-spacing: 0.16em;
    margin-bottom: 0.7rem;
    display: block;
    font-weight: 500;
}
.sem-pov p {
    color: var(--sem-on-navy-strong);
    font-size: 0.98rem;
    line-height: 1.6;
    margin: 0;
}
.sem-pov p + p { margin-top: 0.65rem; }
.sem-pov p strong { color: #ffffff; font-weight: 600; }
.sem-pov a { color: var(--sem-accent-soft); text-decoration: underline; text-underline-offset: 3px; }
.sem-pov a:hover { color: #ffffff; }

/* ============ LAYER PANELS (incumbent vs challenger) ============ */
.sem-layer {
    margin-top: 2rem;
    padding: 1.75rem;
    background: var(--sem-card-bg);
    border-radius: 0.75rem;
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.35), 0 2px 6px rgba(0, 0, 0, 0.1);
    color: var(--sem-ink);
    transition: transform 0.18s, box-shadow 0.18s;
}
.sem-layer:hover {
    transform: translateY(-2px);
    box-shadow: 0 18px 40px -12px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.12);
}
.sem-layer-head {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 1.25rem;
    margin-bottom: 1.1rem;
    padding-bottom: 0.9rem;
    border-bottom: 1px solid var(--sem-rule);
}
.sem-layer-head h3 {
    font-size: 1.35rem;
    font-weight: 500;
    color: var(--sem-ink);
    margin: 0;
    letter-spacing: -0.01em;
}
.sem-layer-tag {
    font-family: var(--sem-mono);
    font-size: 0.68rem;
    color: var(--sem-ink-faint);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    white-space: nowrap;
}
.sem-layer-body {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}
.sem-layer-col h4 {
    font-family: var(--sem-mono);
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--sem-ink-faint);
    margin: 0 0 0.85rem;
    font-weight: 500;
}
.sem-layer-col.challenger h4 { color: var(--sem-accent); }
.sem-layer-col p {
    font-size: 0.92rem;
    line-height: 1.55;
    color: var(--sem-ink-muted);
    margin: 0 0 0.7rem;
}
.sem-layer-col p:last-child { margin-bottom: 0; }
.sem-layer-col p strong { color: var(--sem-ink); font-weight: 600; }
.sem-layer-col p a {
    color: var(--sem-navy);
    text-decoration: underline;
    text-underline-offset: 2px;
    text-decoration-color: rgba(30, 58, 138, 0.35);
    transition: color 0.15s, text-decoration-color 0.15s;
}
.sem-layer-col p a:hover { color: var(--sem-accent); text-decoration-color: var(--sem-accent); }

.sem-pill-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 0.9rem;
}
.sem-pill {
    font-family: var(--sem-mono);
    font-size: 0.72rem;
    padding: 0.25rem 0.65rem;
    border: 1px solid var(--sem-rule-strong);
    border-radius: 999px;
    color: var(--sem-ink-soft);
    background: rgba(15, 23, 42, 0.02);
    letter-spacing: 0.02em;
    transition: background 0.15s, border-color 0.15s;
}
.sem-pill[data-tip] { cursor: pointer; }
.sem-pill[data-tip]:hover { background: rgba(15, 23, 42, 0.06); border-color: var(--sem-ink-faint); }
.sem-layer-col.challenger .sem-pill[data-tip]:hover {
    background: rgba(249, 115, 22, 0.12);
    border-color: var(--sem-accent);
}
strong[data-tip] {
    cursor: pointer;
    text-decoration: underline dotted rgba(30, 58, 138, 0.4);
    text-underline-offset: 3px;
}
strong[data-tip]:hover { text-decoration-color: var(--sem-accent); }

/* ============ SVG DIAGRAM LINKS ============ */
.sem-svg-link { cursor: pointer; transition: filter 0.15s ease, transform 0.15s ease; transform-box: fill-box; transform-origin: center; }
.sem-svg-link:hover { filter: drop-shadow(0 0 8px rgba(249, 115, 22, 0.6)); }
.sem-svg-link:hover rect { stroke: var(--sem-accent); stroke-width: 2.5px; }
.sem-svg-link:focus { outline: none; }
.sem-svg-link:focus-visible rect { stroke: var(--sem-accent); stroke-width: 3px; }

/* ============ CUSTOM TOOLTIP OVERLAY ============ */
.sem-tooltip {
    position: fixed;
    pointer-events: none;
    background: rgba(10, 14, 26, 0.97);
    color: #ffffff;
    border: 1px solid rgba(249, 115, 22, 0.45);
    border-radius: 0.45rem;
    padding: 0.65rem 0.85rem;
    font-family: 'Aeonik Regular', system-ui, sans-serif;
    font-size: 0.8rem;
    line-height: 1.45;
    max-width: 320px;
    z-index: 200;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.12s ease;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.5);
    letter-spacing: 0.005em;
}
.sem-tooltip.show { opacity: 1; visibility: visible; }
.sem-tooltip-hint {
    display: block;
    margin-top: 0.4rem;
    padding-top: 0.4rem;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    font-family: var(--sem-mono);
    font-size: 0.65rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--sem-accent-soft);
}
.sem-layer-col.challenger .sem-pill {
    border-color: rgba(249, 115, 22, 0.4);
    background: rgba(249, 115, 22, 0.06);
    color: #b45309;
}
.sem-pill.star {
    background: rgba(249, 115, 22, 0.18);
    border-color: var(--sem-accent);
    color: #9a3412;
    font-weight: 600;
}
.sem-layer-col.incumbent .sem-pill.star {
    background: rgba(30, 58, 138, 0.12);
    border-color: var(--sem-navy);
    color: var(--sem-navy);
}

.sem-layer-note {
    margin-top: 0.9rem;
    padding-top: 0.8rem;
    border-top: 1px dashed var(--sem-rule);
    font-size: 0.82rem;
    color: var(--sem-ink-faint);
    font-style: italic;
    line-height: 1.5;
}

/* ============ ADJACENT BLOCK ============ */
.sem-adjacent {
    margin-top: 2rem;
    padding: 1.75rem;
    background: var(--sem-card-bg);
    border: 1px dashed var(--sem-rule-strong);
    border-radius: 0.75rem;
    color: var(--sem-ink);
    position: relative;
}
.sem-adjacent::before {
    content: "";
    position: absolute;
    top: 0;
    left: 1.75rem;
    width: 60px;
    height: 2px;
    background: var(--sem-ink-faint);
    border-radius: 0 0 4px 4px;
}
.sem-adjacent-marker {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    font-family: var(--sem-mono);
    font-size: 0.68rem;
    letter-spacing: 0.14em;
    color: var(--sem-ink-faint);
    text-transform: uppercase;
    margin-bottom: 0.9rem;
}
.sem-adjacent-marker .num { color: var(--sem-ink-muted); font-size: 0.9rem; }
.sem-adjacent h3 {
    font-size: 1.4rem;
    font-weight: 500;
    color: var(--sem-ink);
    margin: 0 0 0.7rem;
    letter-spacing: -0.01em;
    line-height: 1.2;
}
.sem-adjacent h3 em { font-style: italic; color: var(--sem-ink-muted); font-weight: 400; }
.sem-adjacent > p {
    font-size: 0.92rem;
    line-height: 1.55;
    color: var(--sem-ink-muted);
    margin-bottom: 1.25rem;
    max-width: 76ch;
}
.sem-adjacent > p a { color: var(--sem-navy); text-decoration: underline; text-underline-offset: 2px; }
.sem-adjacent-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.2rem;
    margin-top: 0.5rem;
}
.sem-adjacent-cell {
    padding: 1rem 1.1rem;
    background: var(--sem-card-bg-2);
    border-radius: 0.5rem;
    border: 1px solid var(--sem-rule);
}
.sem-adjacent-cell .sem-pill {
    border-color: var(--sem-rule-strong);
    background: rgba(148, 163, 184, 0.1);
    color: var(--sem-ink-soft);
}
.sem-adjacent-cell p {
    font-size: 0.88rem;
    line-height: 1.55;
    color: var(--sem-ink-muted);
    margin: 0.6rem 0 0;
}
.sem-adjacent-cell p strong { color: var(--sem-ink); font-weight: 600; }
.sem-adjacent-cell p a { color: var(--sem-navy); text-decoration: underline; text-underline-offset: 2px; }

/* ============ TIER GRID ============ */
.sem-tiers {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.2rem;
    margin-top: 2.5rem;
}
.sem-tier {
    background: var(--sem-card-bg);
    border-radius: 0.75rem;
    padding: 1.6rem 1.5rem;
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.35), 0 2px 6px rgba(0, 0, 0, 0.1);
    color: var(--sem-ink);
    transition: transform 0.18s;
}
.sem-tier:hover { transform: translateY(-3px); }
.sem-tier-num {
    font-family: var(--sem-mono);
    font-size: 0.7rem;
    color: var(--sem-accent);
    text-transform: uppercase;
    letter-spacing: 0.14em;
    display: block;
    margin-bottom: 0.4rem;
    font-weight: 500;
}
.sem-tier h4 {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--sem-ink);
    margin: 0 0 1rem;
    letter-spacing: -0.01em;
}
.sem-tier ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.sem-tier li {
    font-size: 0.88rem;
    color: var(--sem-ink-muted);
    line-height: 1.5;
    padding: 0.55rem 0;
    border-bottom: 1px dashed var(--sem-rule);
}
.sem-tier li:last-child { border-bottom: none; }
.sem-tier li strong { color: var(--sem-ink); font-weight: 600; }
.sem-tier li a {
    color: var(--sem-navy);
    text-decoration: underline;
    text-underline-offset: 2px;
    text-decoration-color: rgba(30, 58, 138, 0.35);
}
.sem-tier li a:hover { color: var(--sem-accent); text-decoration-color: var(--sem-accent); }

/* ============ BENCHMARKS ============ */
.sem-benchmarks {
    margin-top: 2rem;
    padding: 1.6rem 1.75rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px dashed rgba(255, 255, 255, 0.18);
    border-radius: 0.75rem;
}
.sem-benchmarks h4 {
    font-family: var(--sem-mono);
    font-size: 0.7rem;
    color: var(--sem-accent-soft);
    text-transform: uppercase;
    letter-spacing: 0.14em;
    margin: 0 0 1rem;
    font-weight: 500;
}
.sem-benchmarks ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.sem-benchmarks li {
    padding: 0.75rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.92rem;
    color: var(--sem-on-navy-soft);
    line-height: 1.55;
    position: relative;
    padding-left: 1.4rem;
}
.sem-benchmarks li:last-child { border-bottom: none; }
.sem-benchmarks li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--sem-accent);
    font-family: var(--sem-mono);
}
.sem-benchmarks li strong { color: #ffffff; font-weight: 500; }
.sem-benchmarks li a { color: var(--sem-accent-soft); text-decoration: underline; text-underline-offset: 3px; }
.sem-benchmarks li a:hover { color: #ffffff; }

/* ============ METHODOLOGY ============ */
.sem-method-section { padding: 5rem 0; }
.sem-method-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}
.sem-method-col h3 {
    font-size: 1.3rem;
    font-weight: 500;
    color: #ffffff;
    margin: 0 0 1rem;
    letter-spacing: -0.01em;
}
.sem-method-list {
    list-style: none;
    margin: 0;
    padding: 0;
}
.sem-method-list li {
    padding: 0.85rem 0;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    display: flex;
    gap: 1.2rem;
}
.sem-method-list li:first-child { border-top: none; }
.sem-method-k {
    font-family: var(--sem-mono);
    font-size: 0.7rem;
    color: var(--sem-on-navy-faint);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    min-width: 8rem;
    padding-top: 0.2rem;
    flex-shrink: 0;
}
.sem-method-v {
    color: var(--sem-on-navy-soft);
    font-size: 0.92rem;
    line-height: 1.55;
}
.sem-method-v a { color: var(--sem-accent-soft); text-decoration: underline; text-underline-offset: 3px; }
.sem-method-v a:hover { color: #ffffff; }
.sem-method-v strong { color: #ffffff; font-weight: 500; }

/* ============ CTA ============ */
.sem-cta {
    padding: 4.5rem 0;
    background: rgba(0, 0, 0, 0.18);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.sem-cta-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}
.sem-section-label-light { color: rgba(255, 255, 255, 0.55) !important; }
.sem-section-label-light .sem-section-num { color: rgba(255, 255, 255, 0.3); }
.sem-cta-h2 {
    font-size: clamp(1.8rem, 3vw, 2.6rem);
    line-height: 1.1;
    letter-spacing: -0.02em;
    font-weight: 300;
    color: #ffffff;
    margin: 0 0 1.25rem;
}
.sem-cta-h2 em { font-style: normal; color: var(--sem-accent-soft); font-weight: 400; }
.sem-cta-p {
    font-size: 1rem;
    line-height: 1.6;
    color: var(--sem-on-navy-soft);
    margin: 0;
}
.sem-cta-p a { color: var(--sem-accent-soft); text-decoration: underline; text-underline-offset: 3px; }
.sem-cta-p a:hover { color: #ffffff; }
.sem-cta-actions { display: flex; flex-direction: column; gap: 0.7rem; }
.sem-btn {
    display: inline-flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.05rem 1.4rem;
    border: 1px solid rgba(255, 255, 255, 0.22);
    color: #ffffff;
    font-family: var(--sem-mono);
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    transition: all 0.15s;
    border-radius: 0.5rem;
    text-decoration: none;
    background: rgba(255, 255, 255, 0.02);
}
.sem-btn:hover {
    background: #ffffff;
    color: var(--sem-navy);
    text-decoration: none;
    transform: translateY(-1px);
}
.sem-btn-arrow {
    font-family: 'Aeonik Regular', system-ui, sans-serif;
    font-size: 1.15rem;
    transition: transform 0.2s;
}
.sem-btn:hover .sem-btn-arrow { transform: translateX(4px); }

/* ============ CROSS-LAB LINK STRIP ============ */
.sem-crosslink {
    margin-top: 1.5rem;
    padding: 0.9rem 1.25rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 0.5rem;
    font-family: var(--sem-mono);
    font-size: 0.78rem;
    color: var(--sem-on-navy-soft);
    line-height: 1.5;
}
.sem-crosslink strong {
    color: var(--sem-accent-soft);
    font-weight: 500;
    margin-right: 0.4rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 0.68rem;
}
.sem-crosslink a {
    color: #ffffff;
    text-decoration: underline;
    text-underline-offset: 3px;
    text-decoration-color: rgba(255, 255, 255, 0.4);
}
.sem-crosslink a:hover { color: var(--sem-accent-soft); text-decoration-color: var(--sem-accent-soft); }

/* ============ DISCLAIMER ============ */
.sem-disclaimer { padding: 1.5rem 0 0.5rem; }
.sem-disclaimer p {
    font-family: var(--sem-mono);
    font-size: 0.7rem;
    color: var(--sem-on-navy-faint);
    text-align: center;
    margin: 0;
    letter-spacing: 0.05em;
}
.sem-disclaimer a {
    color: var(--sem-accent-soft);
    text-decoration: underline;
    text-underline-offset: 3px;
}
.sem-disclaimer a:hover { color: #ffffff; }

/* ============ RESPONSIVE ============ */
@media (max-width: 960px) {
    .sem-tldr-grid { grid-template-columns: repeat(2, 1fr); }
    .sem-meta { grid-template-columns: repeat(2, 1fr); }
    .sem-tiers { grid-template-columns: 1fr; }
    .sem-method-grid, .sem-cta-grid { grid-template-columns: 1fr; gap: 2rem; }
    .sem-scene, .sem-method-section { padding: 3.5rem 0; }
    .sem-hero { padding: 6rem 0 2rem; }
    .sem-layer-body { grid-template-columns: 1fr; gap: 1.4rem; }
    .sem-adjacent-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
    .sem-tldr-grid { grid-template-columns: 1fr; gap: 1.5rem; }
    .sem-meta { grid-template-columns: 1fr; gap: 1rem; }
    .sem-stat { font-size: 2.4rem; }
    .sem-subnav { top: 60px; }
    .sem-layer { padding: 1.4rem; }
    .sem-tier { padding: 1.25rem; }
    .sem-diagram-wrap { padding: 1rem; }
    .sem-layer-head { flex-direction: column; align-items: flex-start; gap: 0.4rem; }
}

#header.scrolled ~ main .sem-subnav { background: rgba(30, 58, 138, 0.95); }